Oil catch can? Which one are you using?

I have the Moroso oil catch can on my setup.

Was cleaning it out and found that there was still some oil going back out into the intake hose. The catch can does collect a bunch of oil but some still manages to go in and out of the can. The design of the Moroso can could be improved as the seperating wall between the intake and outlet is very short.

I added a taller baffle out of some scrap aluminum sheet extending the seperating wall deeper down into the can so hopefully less oil gets by. Probably will not do anything though haha!

Just curious what else is everyone using for their catch can?

Thanks!

http://www.airwolf.com/aw/products/air-oil-separators

I'm using BT aka Billet Technology catch cans on both my cars.
www.custombilletstore.com
Most people use this catch can. Very popular.

The BT catch can looks to be of similar short dividing wall as the Moroso design.
Check out the tube going back into the intake, I am betting you will find some oil.
If this style is very popular it seems like many people like myself have been getting an inefficient design catch can haha!

I run a BT with a UPR diffuser inside.

I'm running the BT one bolted to the timing cover but I need to move it to the fender. It rubs on my Thunderbird electric fan.

That UPR diffuser looks like a good design. It extends the baffle deeper down into the can as well.

Also apperantly mounting the can onto the engine is wrong because it acts as a heat sink that way. With the catch can being hot next to the engine it doesn't allow the vapors to condense and drop down into the can versus it being mounted somewhere a lot cooler such as the inner fender.

I'll probably re-locate my catch can on the inner fender. Just need some longer hoses

Thats a really good point. Even more reason to move it.

I run the Moroso

I was able to re-locate the catch can onto the firewall and re-use one of my existing hoses so that saved some money. The catch can is way cooler temp wise on the firewall vs. being mounted on the engine.

Another tip is to use heavywall hose as regular rubber hose will collapse from the vacuum under throttle and high RPM.

I used the Aeroquip push lock hose. Good stuff!

This was what I pulled out of the catch can after 10 days of driving to work and back, a few ounces of crap haha!
Definitely trapped some water along with the oil as it is brown instead of the usual black.

Mind you I only live about 15 mins away which may not heat the oil hot enough and it has been raining recently so the humidity is up. The catch can usually traps only oil.

I cleaned it all out and will re-check at the end of next month to see the results

That's not bad at all, mine usually looks like a milkshake, especially in winter. Is that normal or do Gen III's seem to pull an excessive amount of oil through the PCV?

I was told the catch can was a must have for my Jeep srt8. It would collect in the air box, and the throttle body was oily. I found that just running other oil other than Mobil dried it up. I have been using Eneos 5w40 for the last 70,000 km, the intake tract is bone dry.

That is very interesting if true.

I've owned my 2007 Magnum SRT8 for 5 years and have only ran Mobil 1 0w40 in it. I have NEVER had any oil build up in the air box or throttle body.

This is what was caught in the catch can after about a month of daily driving 12 miles to and from work. About 2-3 ounces of oil.

I figure I will check and clean it out every 2-3 months.

The PCV is obviously mean't to vent crank case gases and the crank case is full of oil, so some oil in the PCV system is expected. If there is excessive oil in the PCV that would mean either an improperly designed PCV system or excessive crank case pressure. Since not all Gen III HEMIs experience excessive oil in the intake I would have to suggest the later.

Catch cans originated with the forced induction crowd since high boost pressure result in high crank case pressures. I'm not convinced they are necessary on naturally aspirated engines, especially the Gen III HEMI. After all I've seen several examples of 5.7l HEMIs with 200k miles that never ran a catch can.

If you run them HARD, they will suck oil. This isnt anything new. Ive seen oil in oil breathers on all makes since the PCV was invented.

I guess I don't run my cars hard enough then because the only cars I've ever had problems with excessive oil in the PCV and intake system have been forced induction.

Its just a "preventitive measure" against oil EVER seeing the intake manifold.

Ariel what oil have you been using?

I'm using Mobil-1 10w30.
Arrow Racing recommended 10w30 or 10w40 for the engine and its the same oil I use in my S2000.
Just more convenient that way.

I used Billet Technologies on my 6.1

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